Bobeet jones



(Nomaden.) sheets-sheet 1.

' MOLD BOARD. A 1\To..378,'841i A Patented Feb. 28, 1888.

2u. .TJ e ,e h S s t e e h S 2 S. E N 0. J. DW.

(No'Model.)

MOLD BOARD.

- Patented Feb. z8, '1888;

rest.

UNITED STATES PATENT OFFICE.

ROBERT JONES, OF VVAYNESBURG, OHIO, ASSIGNOR OF ONE-HALF TO CHARLES H.JONES, OF SAME PLACE.

lVlOLDnBOARD.

SPEOIFICATIN forming part of Letters Patent No. 378,841, dated February28, 1888.

Application filed March 10, 1887. Serial No. 230,436. (No model.)

To al@ whom it may concern.- Y

Be 1t known that I, ROBERT JONES, a citizen ofthe United States,residing at I/Taynesburg, in the county of Stark and State of Ohio, haveinvented certain new and useful Improvements in Mold-Boards; and I dohereby declare the following to be a full, clear, and exact descriptionof the invention, such as will enable others skilled in. the art towhich it appertains to make and use the same.

My invention is an improved construction of mold-boards for plows. i

The same is illustrated in the accompanying drawings, and is fully setfort-h in the following specification and claims.

Figure l is a side view of my mold-board. Fig. 2 is a top view of thesame. Fig. 3 is a front view. Fig. 4 is aside view. Fig. 5 is a top viewof a spiral with the mold-board indicated thereon, showing the way inwhich it is cut from the same.

In plowing every furrow describes more or less accurately an arc of twoseparate circles. The iirst is described by the movement upward to aperpendicular position. The second is described by the furrow as itpasses from the vertical position to its position of In order to do thebest possible work, a mold-board should press evenly upon the furrowthroughout the whole Aextent of its movement, and as the movement of thefurrow 1s more rapid after leaving the vertical position the part of themold-board acting thereupon should have a more rapid twist than theforward part of the same. This I accomplish by making the mold-boardfrom a spiral, the axis of which spiral is a curved line or part of acircle having its center on the landward side of the mold-board. Thesize of the circle and the consequent amount of curvature in the axis ofthe spiral dependA upon the size of the plow and on `the length of themoldboard. This construction, it is found, gives the proper twist to therear part of the moldboard to enable it to press upon the furrow equallythroughout its entire length, and the wear upon the same is thereforeeven and the excess of wear upon the rear lower part of the mold-boardis avoided.

In Figs. 4 and 5, A is a section of a spiral. x ac is a dotted lineshowing the axis of the spiral. A is the mold board delineated thereon.It will be seen that the said moldlooard is a part of the said spiral,and' conforms in every part to the same except at the point. Here thedeparture from the form of the scroll is very slight, it being necessaryonly to make such change as will give an approximately straighthorisontal edge along line a b. The line a y indicates the landside ofthe plow. This may be made at a different angle, if desired, as shown bylines a c c z. This would give a greater length in proportion to thewidth; but the operation of the plow would be the same.

Of course it will be understood that although the mold-board is shownin'one piece, in practice it will be preferred to make the usualdivision and have a detachable point similar to other plows in use.

I do not limit myself to the exact form of plow shown, as the principleof construction is capable of being applied to all forms of plows,whether short or long and for whatever uses they are designed.

. 'By reference to Figs. 2 and 5 it willbe seen that the concave side ofthe axis is toward the landside of the plow,or,in other words,curvestoward it.

I am aware that it has beenv proposed to make a mold board of a spiralhaving a straight line for its center; and I am also aware that it hasbeen proposed to make a mold-board of two spirals, forming a straightline from the point of the share to the heel of the mold-board, each ofsaid spirals having a straight line for its center and the centers ofsaid spirals being parallel with each other.

NVhat I c laim,and desire to secure by Letters Patent, is*

l. A mold-board the entire face of which is formed of a part of a singlespiral, the axis whereof is a curved line forming part of a true circlelying on a level with thebottom of the landsideof the plow,substantially as dcscribed. h

2. A mold-board the entire face of which is formed of a part of a singlespiral, and the axis of which is on a level with the bottom of thelandside of theplow and forms part of atrue circle, the concave face ofthe axis facing the landside, substantially as described.

In testimony whereof I afx my signature in presence of two witnesses.

ROBERT JONES.

Witnesses:

LAURA C. JONES, JOHN E. YARGEE.

